Objective: Aberrant right subclavian artery (ARSA) is known to be associated with specific chromosomal abnormalities. However, there is no agreement regarding clinical decisions related to isolated ARSA. This study evaluated the association between ARSA and genetic abnormalities to provide evidence for prenatal consultation and the postpartum management of isolated ARSA.
Methods: This single-center cross-sectional study involved fetuses diagnosed with ARSA between January 2014 and May 2021. A range of data was recorded for each patient, including screening ultrasound, fetal echocardiograms, genetic results, postnatal information, and follow-up records.
Results: ARSA was detected in 151 fetuses, of which 136 were considered isolated cases. The remaining 9.9% (15/151) of cases had cardiac and/or extracardiac abnormalities or soft markers. Data from karyotype analysis and chromosomal microarray analysis (CMA) were available for 56 and 33 (out of 56) fetuses, respectively. Genetic abnormalities were detected in 10.7% of fetuses (6/56). Of these, 4.4% (2/45) and 36.4% (4/11) were associated with isolated and non-isolated ARSA, respectively, with a significant difference between these two groups regarding the frequency of genetic abnormality (p = 0.011). The analysis detected Klinefelter Syndrome (47, XXY) and 16p11.2 microdeletion in two isolated cases. One case each of trisomy 21 and 22q11.2 deletion, and another case of 47, XXY, were detected in fetuses with cardiac anomalies. Partial 5q deletion was found in a fetus with extracardiac malformations. In total, 141 of the fetuses survived after birth; termination of pregnancy was performed for 10 fetuses; only two fetuses had mild symptoms of dysphagia.
Conclusion: ARSA may be an underlying ultrasonic clue for genetic anomalies even in isolated ARSA. Fetuses with isolated ARSA cannot be ruled out for invasive antenatal diagnosis.
Keywords: Aberrant right subclavian artery; chromosomal microarray analysis; genetic abnormalities; karyotyping.